JP2004174434A - Sludge recovering filter cloth and dewatering filter using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sludge recovering filter cloth for effectively and speedily treating and recovering useful and valuable sludge, and at the same time, economically and speedily recovering a useful metal from a plating liquid containing useful plating metal sludge, and a dewatering filter using the same. <P>SOLUTION: The filter cloth for performing solid-liquid separation in which nicks having a width smaller than the major axis of sludge particles to be recovered and a length larger than the major axis thereof are provided only at the bottom face and at the lower part of the side face of the filter cloth in such a distribution state as to become the sufficient filtration speed, is used for performing the solid-liquid separation by circulating and treating the treatment water containing the sludge for sludge filtration recovery, in the dewatering filter. The dewatering filter is characterized using the filter cloth. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a sludge recovery filter applied to various suspensions frequently generated by industrial activities and the like, in particular, a filtration treatment from a plating solution, and a dewatering filter using the sludge recovery filter. About. That is, the present invention provides a sludge collection filter cloth for filtering a plating bath solution (including a plating stripping solution and a plating stripping solution) used to some extent and collecting valuable sludge contained therein, and the sludge collection. The present invention relates to a dehydration filter using a filter cloth.
[0002]
[Prior art]
There are various conventional filtration techniques such as gravity filtration, pressure filtration, and suction filtration. In recent years, many techniques using various membranes, filters, and filter cloths have been studied. However, when used to clean the suspended filtrate due to the peeling of the plating film and at the same time to collect valuable metal sludge, it clogged and found no good filter cloth and filtration equipment. .
[0003]
At present, the sludge collecting filter cloth is apt to be clogged in the conventional gravity filtration apparatus because the filter medium and the filter tank are integrated, and it is troublesome to solve the problem. Although there was a lot of work required, an immersion type gravity filtration device for performing filtration by liquid pressure difference has been proposed (see Japanese Patent Application Laid-Open No. 2000-189718). However, with the conventional filter cloth, solid and liquid cannot be separated efficiently and at high speed even with sludge and sediment which are likely to cause clogging.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide a sludge collecting filter and a dewatering filter using the same. That is, the present invention is to efficiently and quickly treat and collect useful and valuable sludge. At the same time, the present invention is for economically and rapidly recovering useful metals from a plating solution containing useful plating metal sludge.
[0005]
[Means for Solving the Problems]
The present inventor has made intensive studies to solve the above-mentioned problems. As a result, it has been solved by the following means.
(1) Sludge provided with cuts having a width smaller than the major axis of the sludge to be recovered and a length greater than the major axis only in the bottom portion and the lower portion of the side surface of the filter cloth in a distribution such that a sufficient filtration rate is obtained. A filter cloth for solid-liquid separation, which is used in a dehydration filter to circulate and treat a treatment liquid containing the sludge for filtration and recovery, and to separate the liquid and solid. .
[0006]
(2) Filter cloth for solid-liquid separation in which the width of the cut is smaller than the largest major axis of the sludge to be recovered, and the length of the cut is larger than the largest major axis.
(3) Filters provided with cuts having a width smaller than the major axis of the sludge to be recovered and a length greater than the major axis are formed only in the lower portion of the bottom and side surfaces of the filter cloth in such a distribution that a sufficient filtration rate is obtained. A dewatering filtration device for solid-liquid separation, comprising a cloth, wherein the treatment liquid containing the sludge is circulated for treatment to be used for solid-liquid separation.
[0007]
Hereinafter, an example of the sludge collecting filter cloth of the present invention and a dewatering filter apparatus using the same will be described, but the present invention is not limited thereby.
According to the present invention, the cut (A) having a width smaller than the major axis of the sludge to be recovered and having a length greater than the major axis is formed only in the lower portion of the bottom and side faces of the filter cloth in a distribution state in which a sufficient filtration rate is obtained. With this arrangement, the sludge filtration and collection can be efficiently performed. That is, the cut (A) has a slender shape in which sludge to be filtered is long, and at a long diameter thereof, the filter cloth is clogged with eyes and a large amount of sludge is randomly arranged. When deposited on the filter cloth, the deposited sludge itself is clogged, and the liquid cannot be processed smoothly. Therefore, according to the present invention, a large number of the prescribed holes are provided in the filter cloth, and even if there is sludge passing therethrough, most of the sludge to be recovered is not clogged, and most of the sludge to be recovered is deposited by circulation several times. It is trapped in sludge, deposited and collected. That is, the present invention relates to a filter cloth for collecting and dewatering useful sludge while partially circulating the processing liquid, and a dewatering filtration apparatus using the same.
[0008]
ADVANTAGE OF THE INVENTION According to this invention, while using a normal filter cloth, there is no clogging, a filtration speed can be ensured, and a filtration circulation speed is increased, and most sludge can be efficiently and rapidly collected. . That is, the width of the cut is smaller than the largest major axis of the sludge to be collected, and the length of the cut is larger than the largest major axis, so that the processing liquid can be quickly clogged without clogging the filter cloth. The solid-liquid can be quickly separated by circulating.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a schematic cross-sectional view of a dewatering filtration apparatus for sludge recovery according to the present invention.
The treatment liquid B enters the upper space of the filter cylinder (8) from the inlet (1), passes through the filter presser plate (3) having the passage hole (3-1), and enters the filter cloth (4). enter. Then, the liquid that has passed through the filter cloth (4) passes through a net (7), enters the lower space of the filter tube (8) through a hole at the lower part of the filter basket (6), and then passes through a liquid outlet ( From 10), go outside. The net (7) has a three-layer structure (see FIG. 4), and the liquid that has passed through the side of the filter cloth (4) passes between the three-layer network (7) and is filtered. It reaches the lower hole (6-1) of the filtration basket (6), from which it goes out to the lower space of the filtration tube (8).
[0010]
FIG. 2 is an explanatory view showing the structure of the filter cloth (4). That is, the filter cloth has a structure in which cuts (cuts) (A) are formed in the lower side and the bottom of the filter cloth with an appropriate distribution. The size of the cut has a width smaller than the major axis of the sludge to be collected and a length larger than the major axis. That is, the filter cloth cut as described above is used in consideration of the size and characteristics of the sludge to be filtered so that the solid-liquid separation is performed efficiently and quickly. Initially, the inventor tried with a substantially circular hole, but did not achieve efficient separation.
[0011]
Then, the distribution of the cuts is such that the processing liquid has a sufficient filtration rate. That is, it is possible to determine the distribution state by filtering the liquid to be treated on a trial basis.
[0012]
According to the present invention, the treatment liquid is passed and circulated at a sufficient speed through the filter cloth (4) having a large number of cuts (A) as described above. The circulation of the processing liquid is performed until sludge is not present in the processing liquid. As the sludge accumulates inside the filter cloth (4), the flow rate decreases. For example, initially, when the flow rate of 100 to 120 l / min drops to 20 to 15 l / min, the filtration operation is performed. Stop the circulation.
[0013]
FIG. 3 is a cross-sectional view showing how filtration for solid-liquid separation is performed according to the present invention. That is, the filter cloth (4) according to the present invention is provided with a three-layer net (net) (7). Then, the processing liquid B passes through the filter cloth (4) of the present invention as shown by the arrow, flows through the three-layer net (7) as shown by the arrow, and passes through the lower hole of the filtration basket (6). It flows out from (6-1). Therefore, the processing liquid flows out not only from the bottom or lower part of the filter cloth (4) but also from the upper side. The treatment liquid flows most out of the area provided with cuts in the bottom and lower side of the filter cloth (4), but the sludge gradually accumulates and accumulates in that area, so that the flow rate gradually decreases. Go.
[0014]
The net (net) (7) is a three-layer net or net as described above, and is formed of a resin such as polyethylene. The illustrated one has three layers, but may have two or four layers as needed.
[0015]
FIG. 4 is an explanatory sectional view showing the sludge (13) accumulated on the filter cloth (4) and the drying method thereof. When sludge is accumulated on the filter cloth (4) as shown in the figure by circulating the treatment liquid to a certain extent and solid-liquid separated, a valve at the liquid inlet (1) and a liquid outlet (10) are formed. Close the valve. Then, the valve of the air hole (11) provided in the upper space and the valve of the suction port (12) provided on the side surface of the filtration tube (8) are opened. Next, it is connected to a vacuum pump through a valve at the suction port, and vacuum suction is performed. Then, a vacuum is sucked from the lower space in the filtration tube (8), and the inside of the filtration basket (6) is close to a vacuum, and the water inside the sludge (13) is outside the filter cloth as shown by an arrow. Then, the filter cloth (4) comes out. Then, the water passes through the three-layer net (net) (7), exits through the hole in the bottom of the basket (6), and accumulates in the lower stage of the filtration tube (8).
[0016]
As shown in FIG. 4, when vacuum suction is performed, the accumulated water in the sludge (13) is also sucked at the same time, and the sludge is dried. Next, for the filter cloth on which sludge had been deposited and dried, the top cover (2) was then removed, and the filter presser (3) was removed, and the filter cloth (4) was turned over and the filter cloth was attached. By sifting the sludge (13), useful and valuable metal sludge can be collected easily, quickly and easily.
[0017]
In the production of the filter cloth according to the present invention, a polyolefin-based synthetic fiber, for example, a product number P-2304 manufactured by Nippon Kaso Kogyo woven with Pyrene (registered trademark) or the like can be used.
[0018]
The material of the three-layer net (net) (7) used with the filter cloth (4) in the dewatering filtration apparatus of the present invention is a polyethylene resin net.
[0019]
【The invention's effect】
The sludge collecting filter cloth of the present invention and the filter apparatus using the same have the following technical effects by the above-described configuration.
First, precipitates that are useful and valuable, such as electrolytic sludge, but which clog filter cloth and cannot be filtered efficiently can be easily and efficiently filtered off.
Secondly, the present invention provides an apparatus capable of filtering and separating an electrolytic solution at a certain speed without clogging.
[Brief description of the drawings]
FIG. 1 is a sectional view of a dehydration filtration apparatus according to the present invention.
FIG. 2 is a perspective view showing a structure of a filter cloth according to the present invention.
FIG. 3 is a schematic sectional view showing a state of filtration through a filter cloth of the present invention.
FIG. 4 is a schematic cross-sectional view showing sludge accumulated by the filter cloth of the present invention and a state of vacuum suction.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Processing liquid inlet 2 Top lid 3 Filter cloth holder 4 Filter cloth 5 Intermediate wheel 6 Basket 7 Net 8 Filter tube 9 Bottom lid 10 Liquid outlet 11 Air intake 12 Suction port 13 Sludge A accumulated on filter cloth Opened to filter cloth Hole B Treatment liquid C Filtration liquid D Air

Claims (3)

Sludge filtration and recovery in which only cuts having a width smaller than the major axis of the sludge to be collected and a length larger than the major axis are provided only in the lower part of the bottom and side surfaces of the filter cloth in a distribution state that provides a sufficient filtration speed. A filter cloth for solid-liquid separation, wherein the filter cloth is used in a dehydration filtration apparatus for circulating the processing liquid containing the sludge for solid-liquid separation. The filter cloth for solid-liquid separation according to claim 1, wherein the width of the cut is smaller than the largest major axis of the sludge to be recovered, and the length of the cut is larger than the maximum major axis. Only the lower part of the bottom and side faces of the filter cloth is provided with filter cloth having cuts having a width smaller than the major axis of the sludge to be recovered and having a length larger than the major axis in such a distribution that a sufficient filtration speed is obtained. A dewatering filtration device for solid-liquid separation, wherein the treatment liquid containing the sludge is circulated and processed to be used for solid-liquid separation.

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